Hartford Technologies Blog

How to Select the Best Grease for Custom Bearing Applications

Posted: May 19, 2017 2:37:46 PM

At Hartford Technologies, we are committed to creating custom bearing assemblies that are built to last. Making use of the right grease, though, is a vital part of maintaining your custom bearing assemblies and without it, the wear and tear on a bearing assembly will be off the charts. With that in mind, outlined below are a few of the different factors that go into choosing the right grease.

Viscosity

One of the most important aspects of a grease is its viscosity. In determining the optimum viscosity for the grease you put into your custom bearing assembly, you will want to look at the speed factor of your bearings and use that number to select an optimum viscosity from a chart that should be readily available from the manufacturer you get your grease from. This speed factor, commonly denoted as DN, can be calculated by multiplying your RPM by the bearing bore.

Additives

Greases will often have a number of additives put into to them that are designed to increase the performance of the grease. These additives include:

Antifoam agents

Rust inhibitors

Corrosion inhibitors

VI Improvers

Antioxidants

Extreme Pressure

Demulsibility

Depending on your specific bearing type and application, you will want to look for grease that has the additives it will need to perform the best in the conditions it will be up against.

Grease Consistency

The consistency of a grease is related to its viscosity, though it is important to note that a grease with a high viscosity can still have a low consistency, and vise versa. In order to determine the optimum consistency for your grease, you will need to take the speed factor of your bearings (DN) as well as the operating temperature of the grease and use those numbers to select the best consistency from a chart provided by the manufacturer of your grease.

As for the additives that are used to thicken a grease, there are a few options available, each with their own specific pros and cons. The most common thickeners are lithium soap, lithium complex, and polyurea. Lithium soap is the least expensive option and is used in many general purpose greases. It has good performance at moderate temperatures, but for high operating temperatures you will want to choose a grease that is thickened with polyurea or lithium complex. Both of these thickeners display great performance at high operating temperatures, and both also have high bleed resistance and oxidation stability.

Choosing the Best Grease for Various Custom Bearing Applications

Using the factors outlined about, you should be able to choose the right grease for any number of applications. There are, however, popular choices and special considerations depending on your intended applications.

For food/beverage industries, you will want to use a grease with an H1 rating so that it will be completely safe and tasteless if it comes into contact with the food. For the automotive industry, look for quality automotive greases that are made to withstand high operating temperatures. For custom bearing assemblies used in the medical industry, a wide range of greases are used, though depending on where in the device the grease is going, you will want to be careful to choose a grease that is completely safe to the patient and designed for use in medical devices.

Conclusion

If you want the best performance, choosing the best grease for your custom bearing assembly isn't quite as simple as choosing a grease at random. To ensure optimum functionality and longevity of your bearing assembly, you will want to select a grease that has the correct viscosity, additives, and consistency.

Of course, there's no sense in putting a great grease inside a mediocre bearing assembly. At Hartford Technologies, we strive to produce custom bearing assemblies that are built to last and always perform exactly as intended. If you would like to learn more about our custom bearing assemblies, we invite you to contact us today.